‘If you were from another country and you watched this based on body language, people would think that Mitt Romney was already the President,’ she added.

Moreover, the former governor of Massachusetts took part in 19 debates during the Republican primary season from June 2011 to February 2012.

The President, on the other hand, has mostly delivered speeches on formal occasions such as the State of the Union or in front of partisan crowds at campaign events, and may therefore be unaccustomed to the cut-and-thrust of a head-to-head encounter.

‘I don’t think anybody’s ever spoken to him like that over the last four years,’ CNN analyst David Gergen said. ‘I think he found that not only surprising, but offensive in some ways.’